Bioavailability generic drugs

The other computation is that of relative bioavailability. This calculation is determined when two products are compared to each other, not to an intravenous standard. This is commonly calculated in the generic drug industry to determine that the generic formulation (e.g., a tablet) is bioequivalent to the original formulation (e.g., another tablet). Thus, bioavailability is not routinely calculated in an individual patient but reserved for product development by a drug manufacturer. However, it is important to have an idea of how formulations or routes of administration differ with respect to bioavailability so as to allow proper dosage adjustment when changing formulations or routes of administration. 

If drugs have the same bioavailability (i.e., the same AUC) they are said to be bioequivalent. This is a particularly important aspect in the development of generic drugs (discussed later). However, it should be appreciated that bioavailability refers ultimately to plasma concentration per se. It does not tell us anything about therapeutic... 

The measurement of the bioavailability and bioequivalence of drug dosage forms is commonplace. The numerous reasons for the increased use of such studies include rapid growth of the generic drug industry an increased awareness of the effect of dosage form on the rate and extent of drug absorption the development of more sensitive and reliable analytic methods to... 

SCIENTIFIC BASIS FOR GENERIC DRUG PRODUCT EQUIVALENCY BIOAVAILABILITY-BIOEQUIVALENCY... 

A city clinic is considering the substitution of generic drugs in order to save money. The clinical pharmacologist is asked to advise on the bioavailability of the generic products. She informs the head of the clinic that the bioavailability of drugs is... 

The topic of generic bioequivalence pertains to the relative bioavailability of different versions of the same drug product, all of which may be available in the marketplace at the same time. Thus, if we continue our consideration of the example introduced in the previous section of this chapter, let us suppose that the innovator did obtain approval to market F3. Initially F3 was the only product available in the marketplace. However, when the relevant patents held by the innovator have expired, other pharmaceutical... 

Christians U, First MR, Benet LZ (2000) Recommendations for bioequivalence testing of cyclosporine generics revisited. Ther Drug Monit 22 330-335 CPMP (2000) European Medicines Agency. Committee for Proprietary Medicinal Products. Note for guidance on the investigation on bioavailability and bioequivalence. CPMP/EWP/QWP/1401/98.http //www.emea.europa.eu/pdfs/human/qwp/140198en.pdf. Cited 30 Dec 2008... 

The BCS also predicts the possibility of obtaining an in vitro/in vivo correlation. Justification of a biowaiver is based on a combination of the BCS classification of the drug substance and a drug product dissolution profile comparison. In all these instances, an anchor with a bioavailable product is established. Specifically, to obtain a biowaiver for an IR generic product ... 

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